Table of Contents
Advertisement
Hexadecimal dump
This feature is useful for programmers who are debugging printing programs and want to
see the actual codes the printer is receiving. (Some computers change the codes the
programmer intended.)
In this mode, all data received will be printed in a hexadecimal dump format, rather than
the control codes being acted on as command codes.
This mode is accessed with the following procedure:
1. While holding the I
I
button down, turn power ON. A beep tone will be
heard.
2. Begin printing. In place of the usual printout you will get a formatted dump showing
exactly what data the printer receives. Each line presents sixteen characters, their
hexadecimal codes to the left and printable characters printed on the right.
3. Attheendofthehexadecimaldump,setthepfinteroff-line
withthe I ON
]
button.
This is necessary to print the last line.
The following BASIC program is a simple test you can run in hexadecimal mode:
10 WIDTH " LPT 1 : " , 255
20 FOR 1=0 TO 255
30 LPRINT
CHR$ ( I ) :
40 NEXT I
50 LPRINT
END
If your system passes the codes directly to the printer without changing them, you will get
a printout like Figure 4-7.
00
01
02
0.3 04
05
06
07
Oh 09
[M
OH OC
(01) OF
OF
10
11
12
13
14
15
16
17
I b
1Y 1A i B I (:
1D 1!- 1F
20
21
22
23
24
25
26
27
2b
29
2A 2B
2(:
2D 2E
2F'
30
31
32
33
34
.35 36
37
3b
39
.3A 3B 3C 31) 3E
3E"
40
41
42
43
44
45
46
47
48
49
4A. 4B 4C 4U 41? 4F
50
51
52
53
54
55
5b
.57
.58
59
5A 5B
5C 51) 5E
5P'
60
61
62
6.3 64
65
66
67
66
69
6A OF! bC bI) bF 6F-
70
'71 72
73
74
75
76
77
78
79
7A 7B 7C 7D 7E
7fi'
80
81
82
83
84
55
86
87
86
$39 6A
hB
bC
hI) SE
bF
90
91
92
93
94
95
96
97
98
99
9A
9B 9(;
91) 91? 9F"
AO A 1 A2 A3
.A4 .A5 .Ab A7
AS .A9 .AA AR AC AD .4P AF
BO B1 B2
B3 134 B5
Bb B7
B8
B9
nA
Hi? 13c [it)
BP: BP"
co
c 1 C2 C3 C4 [:5
C(-J C7
CS C9 CA (;11 CC CD CE CF'
DO D 1 D2 F)3 04
D5 Db 1)7
1)8 1)9 DA F)B IX; DE I)F I)h
EO E 1 E2 h;.3 !s4 E5 I-6 !-7
E8 E9 F:A F;B EC El) F:P: EF'
FO F 1 F2 F:3 F4
F5
F"6 E-7
FEi F9
E"A FB FC E'D F1- F'P'
. . . . . . . . . . . . . . . .
. . . . . . . . . . . .
; : ;$O/o&
(
)?<+,– ./
0
;
?
B
I JKLMNO
PQRSTUVWXY'Z
[ \
1
' a
i j k
p
{ I }
. . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . .
F
4
S
h
d
Most BASICS, however, are not quite that straightforward. For example, the IBM-PC will
give you a printout similar to Figure 4-8.
When the IBM-PC BASIC interpreter sends hex code OD(carriage return) it adds an extra
hex OA (line feed). Hex code 1A (end-of-file) also gets special treatment: the interpreter
does not send it at all. This can cause problems with graphics or download character data.
However, you can solve this problem by changing line 30 in the preceding program and
adding the coding shown below.
Chapter4
CONTROL PANEL OPERATIONS
27
Advertisement
Table of Contents
